MECH 211 Test 1 Fall 2004

MECH 211

Fall 2004

Test 1

Due September 27, 2004 at the start of class.

Show all work. Any force existing in an equilibrium equation must also be denoted on anappropriate and correct free body diagram. Clearly indicate final answers.

This test is taken under the Rice Honor Code system. You may consult only the textbook(Bedford and Fowler), notes that you have personally taken, and any material downloaded fromthe course website. You may use a calculator, including programmable calculators. The testmust be taken during a 3-hour period, with an optional 30-minute break.

Time started:__________________________________

Time finished:_________________________________

Pledge:_______________________________________

MECH 211 Test 1 Fall 2004

1. The pipe assembly is subjected to the 20-lbforce. The angles between the direction ofthe force and the x, y and z-axes are 60°, 120°and 45° respectively. Determine (a) themoment due to this force about point O, and(b) the moment of this force about the axispassing through points A and O.

2. (Figure to the right.) The weightlessbeam is in equilibrium and subjectedto the distributed load as shown.Determine the tension in the rope andthe reactions at C.

3. (Figure to the left.) If the maximum force thatany of the truss members can support is 8 kN intension or 6 kN in compression, determine themaximum force P that can be supported by thestructure at joint D. Note that the support at jointE has an identical effect as a rolling support.

4. The end C of the two-bar linkage rests on top of the center of theuniform density 50-kg block D. If the coefficients of static frictionat C and E are µC = 0.6 and µE = 0.3, determine the largest verticalforce P that can be applied at B without causing motion at any pointin the system. What type of motion is caused if P is greater thanthis critical force? Neglect the mass of the bars in the linkage.